1. Field of the Invention
The present invention relates to an image processing apparatus and method for processing captured image data read from an image capturing unit.
2. Description of the Related Art
Some of the recent image capturing elements can switch among “all-pixel reading mode”, “partial reading mode”, and “thinned-out reading mode”. In the “all-pixel reading mode”, signals are read from all of the pixels on an image capturing element. In the “partial reading mode”, signals are read only from pixels located in an arbitrary region on the image capturing element. In the “thinned-out reading mode”, signals are read while skipping pixels on the image capturing element at an arbitrary interval. The “partial reading mode” and the “thinned-out reading mode” may be combined, that is to say, signals may be read while skipping pixels located in an arbitrary region at an arbitrary interval.
Conventionally, there has been a surveillance camera system incorporating an image capturing element that can change its reading mode.
US 2009/0160947 A1, granted a patent, discloses a system for reading a designated region on an image capturing element at a short time interval, and performing thinned-out reading of other regions in multiple batches at a longer time interval. US 2009/0160947 A1 also discloses a system in which an entire-region thinned-out image is displayed on the left side of a monitor, and a partial image is displayed on the right side of the monitor in an enlarged manner.
Furthermore, an image capturing system is configurable that continuously reads only a specific region but does not read regions other than the specific region.
However, the image capturing system disclosed in US 2009/0160947 A1 does not explicitly display the frequencies at which entire-region thinned-out images and partial images are read. This poses the problem that the frequencies at which the entire-region thinned-out images and partial images are updated cannot be visually perceived. In addition, the skip interval for image reading cannot be visually perceived.
Similarly, in the case where only a specific region is continuously read and regions other than the specific regions are not read, it is not possible to visually perceive how long the regions other than the specific region have been left without being updated.